Re: [orchestra] Conversation issues with master-detail
Hi! I am trying to create a master-detail screen scenario and am following the best-practices guide in the wiki (the simple CRUD cycle - http://wiki.apache.org/myfaces/A_simple_Crud_Cycle) and it does not actually work. Am I doing something wrong? Unhappily the author of this page did not say which scope to use for the master and detail view. @Werner, can you comment on it please. When I do a save on the DetailView, if I call refreshList on the MasterView after saving using the DetailView instance of the BO, the list does NOT contain my changes. I understand why this is happening. The BO in the MasterView has its own entity manager as it is in a different conversation than the DetailView. It does not help to do Conversation.getCurrentInstance().invalidate() in the DetailView before doing a list refresh on the master view as there is still nothing to force the entity manager in the MasterView to dump its cached objects. Yep, this invalidate will just invalidate the detail conversation, not the one of the Master. Some possible ways are: 1) If Master and Detail are both in two different conversations (flash) simply avoid referencing the Master from your Detail. When navigating to the Detail this will end the Master conversation automatically, on navigating back the Master will be a fresh instance with a fresh EntityManager ... thus, should load the data again. 2) End the Master conversation from within the Detail bean (not recommended) ConversationUtils.invalidateIfExists(name of master conversation). Name of name of master conversation is the one you configured using orchestra:conversationName on the bean definition or the bean-name if you didn't use that configuration. 3) Use the same conversation for the Master and Detail. Do this by using the orchestra:conversationName=editXYZData on both bean definitions. Then they use the same EntityManager and you are fine anyway. Putting both in the flash scope will handle the cleanup once the user navigates away. This is the way I'll mostly use. As a side note, if the Master page allows to define some filter, I often put them into their own bean in a separate conversation of type manual. That way, even if the flash conversation ends the user input won't be lost. For sure, this filter bean should not hold any entity as you might run into problems if passing entities from one conversation to another one. Hope this helps! Ciao, Mario
Re: [orchestra] Conversation issues with master-detail
Thanks. I did figure out some of these approaches, but was wondering if I was missing something as none of them match the example! Of course, the proposed solutions that involve sharing the conversation between master and detail or invalidating the master from the detail mean that calling refreshMaster (as in the example) is pointless as it will have to redo that anyway when rebuilding the conversation. It just made me wonder under what conditions (conversation-wise) the example actually works, because I could not figure one out that handled both save and cancel properly! I did come up with one more solution that might be considered a bit dangerous. When the master view needs its object list, it goes to the detail view to get it (detail in its own flash conversation). This way there is only one entity manager involved (the detail view version), but the master and detail conversations are always both running (the detail just comes and goes more often). The danger is you have to make sure you never actually do anything transactional in the master with the objects using the BO in the master view conversation as the objects belong to the entity manager in the detail. Thanks again for your input. At least I know I'm on the right track. Rick Mario Ivankovits wrote: Hi! I am trying to create a master-detail screen scenario and am following the best-practices guide in the wiki (the simple CRUD cycle - http://wiki.apache.org/myfaces/A_simple_Crud_Cycle) and it does not actually work. Am I doing something wrong? Unhappily the author of this page did not say which scope to use for the master and detail view. @Werner, can you comment on it please. When I do a save on the DetailView, if I call refreshList on the MasterView after saving using the DetailView instance of the BO, the list does NOT contain my changes. I understand why this is happening. The BO in the MasterView has its own entity manager as it is in a different conversation than the DetailView. It does not help to do Conversation.getCurrentInstance().invalidate() in the DetailView before doing a list refresh on the master view as there is still nothing to force the entity manager in the MasterView to dump its cached objects. Yep, this invalidate will just invalidate the detail conversation, not the one of the Master. Some possible ways are: 1) If Master and Detail are both in two different conversations (flash) simply avoid referencing the Master from your Detail. When navigating to the Detail this will end the Master conversation automatically, on navigating back the Master will be a fresh instance with a fresh EntityManager ... thus, should load the data again. 2) End the Master conversation from within the Detail bean (not recommended) ConversationUtils.invalidateIfExists(name of master conversation). Name of name of master conversation is the one you configured using orchestra:conversationName on the bean definition or the bean-name if you didn't use that configuration. 3) Use the same conversation for the Master and Detail. Do this by using the orchestra:conversationName=editXYZData on both bean definitions. Then they use the same EntityManager and you are fine anyway. Putting both in the flash scope will handle the cleanup once the user navigates away. This is the way I'll mostly use. As a side note, if the Master page allows to define some filter, I often put them into their own bean in a separate conversation of type manual. That way, even if the flash conversation ends the user input won't be lost. For sure, this filter bean should not hold any entity as you might run into problems if passing entities from one conversation to another one. Hope this helps! Ciao, Mario -- View this message in context: http://www.nabble.com/-orchestra--Conversation-issues-with-master-detail-tf4894353.html#a14030765 Sent from the My Faces - Dev mailing list archive at Nabble.com.
[orchestra] Conversation issues with master-detail
I am trying to create a master-detail screen scenario and am following the best-practices guide in the wiki (the simple CRUD cycle - http://wiki.apache.org/myfaces/A_simple_Crud_Cycle) and it does not actually work. Am I doing something wrong? Here is what I have: MasterView has a BO which it uses to fetch a list of all target objects (just like in the example). DetailView is in its own detail related flash conversation (as mentioned in the bottom of the example), and has a reference to the BO as well. (manual/flash makes no difference whatsoever) When I do a save on the DetailView, if I call refreshList on the MasterView after saving using the DetailView instance of the BO, the list does NOT contain my changes. I understand why this is happening. The BO in the MasterView has its own entity manager as it is in a different conversation than the DetailView. It does not help to do Conversation.getCurrentInstance().invalidate() in the DetailView before doing a list refresh on the master view as there is still nothing to force the entity manager in the MasterView to dump its cached objects. The example is quite unclear on many details and was wondering if I am doing something wrong here. I have found several ways to make it work as expected, but they are NOT like the example, and are a bit more difficult to figure out as to what is going on without documentation. My test is extremely simple and is NOT working as advertised! Can anyone help? -- View this message in context: http://www.nabble.com/-orchestra--Conversation-issues-with-master-detail-tf4894353.html#a14017094 Sent from the My Faces - Dev mailing list archive at Nabble.com.